Skip



P 1962 J. w. CLARK 3,052,367

SKIP

Filed D80. 7, 1959 3 Sheets-sheet 1 INVENTOR. F e James W. CLARK ATTORNEQY J. W. CLARK Sept. 4, 1962 SKIP 3 Sheets-Sheet 2 Filed Dec. 7, 1959 INVENTOR. James W. CLARK ama; W

ATTORNEY P 4, 1962 J. w. CLARK 3,052,367

SKIP

Filed Dec. 7, 1959 3 Sheets-Sheet 3 FIG--4 F\ 5 I INVENTOR.

James W.CLARK.

BYJW (u. M

A-r-rom av United States Patent Ofilice dfififih? Patented Sept. 4, W952 3,052,367 SKE James W. Clark, Iron Mountain, Mich., assignor to Lake Shore, inc, Iron Mountain, Mich, a corporation of Michigan Filed Dec. 7, 1959, Ser. No. 857,723 13 (Ilaims. or. 214-741) This invention relates to a skip and particularly to a front discharge skip having a mechanically actuated dumping door.

As production facilities in the shaft increase, the skips became the limiting factor on mine production and as a result the development of bottom dump skips has received considerable attention in recent times. The advantages of bottom dump skips in general are that they require less headframe heights and dump in a shorter time which means more skip trips per day and, hence, the output of the mine can be increased. The present invention represents an improved skip of the type having a front opening door adjacent the bottom of the skip.

The principal object of this invention is to provide a skip of relatively simple construction which can be quickly dumped while remaining in the guide timbers.

Another object is to provide a skip having an improved door operating toggle mechanism which forces the door closed to prevent spillage and also utilizes the weight of the load to open the door once the linkage moves over center to thereby minimize the force transferred to the headframe during dumping.

Another object is to provide a skip having a retractable chute means adapted when dumping to eliminate flying particles, reduce dust and prevent material from falling back down the shaft between the skip and loading bin.

Another object is to provide a skip which has a simple and reliable means for locking the door and door operating mechanism in the closed position to thereby eliminate all possibility of spillage during travel and make the skip watertight.

A skip embodying this invention comprises a body having a bottom which slopes to a discharge opening in the front wall of the skip. A dumping door is pivotally mounted along the upper edge of the discharge opening and a door operating toggle mechanism is provided to open and close the door with a positive action. The toggle mechanism is actuated by a pair of dump rollers working within a pair of scrolls located in the headframe of the mine. With the above design the skip can be dumped while still in the guide timbers and with the skip maintaining its upright position at all times. The travel of the skip in the dump scrolls is relatively short (about three feet) providing a reduced dump time to thus increase mine production.

The toggle mechanism includes a pair of dumping arms pivotally mounted on the skip and operatively connected to the dumping door by a pair of links. The parts move past an over center position when the door is completely closed to thereby force the door tightly into its closed position. When opening the door, the weight of the load acting on the door is utilized once the linkage passes back over center and thus only very little force is transferred to the headframe during dumping.

A simple and reliable means including a pivoted safety hook and a movable door locking member are provided to lock the door and the door operating toggle mechanism in the closed position during travel of the loaded skip in the mine. This insures that the door will not drift open during travel due to wear in the parts of vibration of the skip in travel.

To minimize the spillage during dumping a retractable chute means operable in response to actuation of the door operating mechanism is provided. Such means includes a pivoted bridge plate and a pair of vertical side skirts on the door which cooperate when retracted to form a chute-like extension at the discharge opening of the skip.

Other objects and advantages will be pointed out in, or be apparent from the specification and claims, as will obvious modifications of the single embodiment shown in the drawings, in which:

FIG. 1 is a view in side elevation of a skip embody ing my invention with the dumping door closed and with some parts broken away;

FIG. 2 is a view similar to FIG. 1 but with the dumping door open;

FIG. 3 is a front elevation view of the skip taken along line 3-3 of FIG. 1;

FIG. 4 is a sectional view taken along with 4-4 of FIG. 3; and

FIG. 5 is a front elevation view of the skip taken along line 55 of FIG. 2.

Referring to the drawings in detail, the skip com.- prises a body 10 having an open top 12 for filling and a bottom 14 which slopes downwardly and forwardly to a vertical discharge opening 16 in the lower front face of the body. The skip is supported in a mine shaft by a wire rope connected to a hoist mechanism and is guided in a conventional manner by guide timbers mounted in the shaft for engagement by guide rollers mounted on stringers l8 fastened to skip body it The skip has a dumping door 20 pivotally supported on a shaft 2.2 mounted along the upper edge of discharge opening id for swinging movement between a closed position shown in FIG. 1 to a dump position shown in FIG. 2.

Door 2% is opened and closed with a positive action by a toggle mechanism 23. Mechanism 23 includes a pair of dumping arms 24- operatively connected to the door by a pair of links 26 which are pivotally connected between the central portions of arms 24 and side skirts 28 on the door at pivots 25 and 27, respectively. Dumping arms 24 are pivotally supported on the skip body by means of a shaft 30 mounted between horizontal channel supports 32 fastened to stringers 18, as shown.

The door opening mechanism is actuated as the skip is hoisted vertically by means of a pair of dump rollers 34 mounted on arms 24 by a shaft 36. Rollers 34 are adapted to work within a pair of dump scrolls 33 mounted in the headframe of the mine and located in the path of movement of the rollers. hooks 40 each having an actuating roller 42 and a hooked end 43 are pivotally mounted on shaft 36 as shown. Keepers 45 fastened to stringers 18 on opposite sides of the skip body are engaged by hooked ends 43 of safety hooks 40 as shown in FIG. 1 to thereby lock main dump roller shaft 35 to the body of the skip while the skip is traveling in the shaft. Hooked ends 43 of the safety hooks are weighted sufficiently to insure that they will remain engaged with keepers 45 during such travel.

With the door 20 in the closed position (FIG. 1), dump roller shaft 36 rests in notches 44 cut in the forward edges of parallel side walls 46 of body 10 which extend outwardly from the inwardly sloping front face 48 of the body. With the parts of toggle mechanism 23 in the fully closed position (FIG. 1) pivots 25 between dumping arms 24 and links 26 will be slightly to the right (on the door closing side) of an imaginary line 49 between the pivot 30 for arms 24 and the pivots 27 between links 26 and side skirts 23. With the parts in this position, the force exerted on door Zil by the weight of the material in the A pair of safetycompletely water-tight skip by the provision of a suitable seal (not shown) at the discharge opening. Furthermore, as previously explained, the weight of the load acting on the door will not produce a force component tending to swing arms 24 in the door opening direction but will instead tend to move the toggle mechanism further in the door closing direction.

As the skip is hoisted into the headframe of the mine, rollers 4-2 of safety hooks 4% will engage scrolls 38 which, in turn, pivot the hooks in a counterclockwise direction on shaft 36 and thereby unlatch hooked ends 43 from keepers 4.5. Thus, main dump roller shaft 36 is unlatched from the skip body to permit free movement of dumping arms 24. As hoisting continues, dump rollers 34' follow safety hook roller 42 into scrolls 38 to thereby move mechanism 23 from the closed position shown in FIG. 1 to the open position shown in FIG. 2. As arms 24 are swung outwardly by the action of rollers 34 in scrolls 38, link 26 operates to swing door open with a positive action and thereby dump the contents of the skip into a suitable receptacle 50 mounted in the headframe of the mine. After pivots pass back over center the weight of the load acting on the door helps the door to open and thus only a relatively small force is transferred to the headframe during dumping.

To keep spillage to a minimum when dumping the skip, door 20 is provided with vertical side skirts 28 which cooperate with a pivoted bridge plate 5 5- (FIG. 2) to channel the flow of material from the skip into receptacle 50. Bridge plate 54 is mounted for pivotal movement with arms 24- by brackets '56 from a retracted position beneath the skip (FIG. 1) to an operative position (FIG. 2). When plate 54 is retracted it lies within the outer periphery of the skip body and thus does not interfere with the vertical travel of the skip in the shaft. As the door is opened by the action of arms 24, plate 54 is pivoted (FIG. 2) so that it lies substantially parallel with sloped bottom 14 of the skip to thereby form an extension of such bottom to bridge the clearance space between discharge opening 16 and receptacle 50. As clearly shown in FIG. 2, side skirts 28 on door 20 cooperate with bridge plate in the dump position to form a chute-like extension at the discharge opening. This eliminates flying particles, reduces dust and prevents material from falling into the shaft during dumping.

After the skip has been dumped door 20 is closed with a positive action as the skip is lowered from the headframe into the shaft. Dump rollers 34 working in scrolls 38 will swing arms 24 back to the FIG. 1 position. Rollers 42 will follow the dump rollers out of the scrolls to thereby pivot safety hooks 4th into engagement with keepers 45 to positively lock shaft 36 and arms 24 to the skip body.

To insure positive locking of door 20, a pair of door locking members 58 adapted for engagement with the lower edge 60 of the door is provided. Members 58 are mounted on arms 24 and adapted to swing with the arms as the door is closed to engage edge 60 and put the final squeeze on the door as the dump rollers move out of the scrolls and the mechanism is locked to the skip by hooks 40. Locking members 58 thus serve to provide a watertight door (by use of a proper seal) and prevent the door from drifting open slightly due to pin and bushing wear.

While the normal travel movement of the skip shown in the drawings is vertical it should be understood that a skip embodying the present invention could be made to operate satisfactorily with a normal travel movement at an angle with the vertical.

From the foregoing it will be apparent that a skip of the above design embodies several advantageous features. First, it is noted that the skip can be dumped while still in the guide timbers with the skip maintaining its upright position at all times. The travel of the skip in the dump scrolls is relatively short providing a reduced dump time to thus increase mine production. The door operating mechanism is actuated with a minimum of thrust on the dump rollers and scrolls to thereby reduce stresses on the headframe and guide timbers. The door is opened and closed with a positive action and a simple, reliable means (hooks 40 and members 58) are provided to lock the door and operating mechanism in the closed position during travel of the loaded skip in the shaft. Finally, by the cooperation of bridge plate 54 and skirts 28 in the open position (FIG. 2) spillage during dumping is kept to a minimum.

Although but one embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

I claim:

1. A skip adapted for travel in a mine shaft comprising, a skip body having a bottom sloping to a discharge opening in the lower portion thereof, a dumping door pivotally mounted at said discharge opening to control flow through said opening, a door operating mechanism adapted when actuated to open and close said door with a positive action, actuator means adapted to actuate said operating mechanism to open and close said door in response to the normal travel movement of said skip, first locking means mounted on said door operating mechanism and operatively connected to said actuator means, said first locking means operable in response to the normal travel movement of said skip to lock and unlock said operating mechanism, and second locking means mounted on said door operating mechanism and operable in response to the normal travel movement of said skip adapted to lock and un- 0 look said door.

2. A skip according to claim 1 in which said first locking means includes a safety hook pivotally mounted on said operating mechanism and adapted to engage a keeper on said skip body to lock said door operating mechanism in its closed position.

3. A skip according to claim 1 in which said second locking means includes a door locking member mounted on said operating mechanism and adapted to engage the free swinging edge of said door as said door is actuated to its closed position to thereby lock said door in its closed position.

4. A skip according to claim 1 in which said discharge opening is in the front face of said skip and said door is pivotally mounted along the upper edge of said discharge opening, said skip further characterized by a door operating mechanism including a dumping arm pivotally mounted on said skip beneath said discharge opening and operatively connected to said door by a link pivotally connected between said arm and said door, said operating mechanism when in its fully closed position having the pivot between said arm and said link lying on the door closing side of an imaginary line between the pivot point of said arm and the pivot between said link and said door.

5. A skip according to claim 1 in which there is a bridge plate pivotally mounted on said skip beneath said discharge opening and operatively connected to said door operating mechanism, said plate adapted for movement outwardly from under said skip body as said door is opened to a position whereby it forms an extension of said skip bottom to prevent spill-age during dumping.

6. A skip adapted for travel in a mine shaft comprising, a skip body having a bottom which slopes to a discharge opening in the front wall of said skip, a dumping door pivotally mounted along the upper edge of said discharge opening, a door operating mechanism adapted when actuated to open and close said door with a positive action, actuator means adapted to actuate said operating mechanism to open and close said door in response to the normal travel movement of said skip, said operating mechanism including a dumping arm pivotally mounted on said skip and operatively connected to said door, said arm adapted to be pivoted by said actuator means to open and close said door, said actuator means including a dump roller on said dumping arm adapted to work within a stationary dump scroll during the normal travel movement of the skip to thereby pivot said dumping arm and open and close said door, a door locking member mounted on said dumpin arm adapted to engage the free swinging edge of said door along the bottom edge of said discharge opening as said arm is pivoted in its door closing direction to thereby lock said door in its closed position, and a safety hook pivotally mounted on said dumping arm and adapted to engage a keeper on said skip body to lock said door operating mechanism in closed position, said safety hook having a roller mounted thereon adapted to work within said stationary dump scroll to thereby latch and unlatch said hook from said skip during the normal travel movement of the skip.

7. A skip according to claim 6 in which said arm is pivotally mounted on said skip beneath said discharge opening and is operatively connected to said door by a link pivotally connected between said arm and said door, said operating mechanism when in its fully closed position having the pivot between said arm and said link lying on the door closing side of an imaginary line between the pivot point of said arm and the pivot between said link and said door.

8. A skip according to claim 6 in which there is a bridge plate pivotally mounted on said skip beneath said discharge opening and operatively connected to said door operating mechanism, said plate adapted for movement outwardly from under said skip body as said door is opened to a position whereby it forms an extension of said skip bottom to prevent spillage during dumping.

9. A skip adapted for travel in a mine shaft comprising, a skip body having a discharge opening in the front wall of said skip, a dumping door pivotally mounted along the upper edge of said discharge opening, a door operating mechanism adapted when actuated to open and close said door with a positive action, and actuator means adapted to actuate said operating mechanism to open and close said door in response to the normal travel movement of said skip, said operating mechanism including a dumping arm pivotally mounted on said skip and operatively connected to said door by a link pivotally connected between said arm and said door, said arm adapted to be pivoted by said actuator means to open and close said door, said dumping arm when in its fully closed position having the pivot between said arm and said link lying on the door closing side of an imaginary line between the pivot point of said arm and the pivot between said link and said door.

10. A skip according to claim 9 in which said dumping arm is pivotally mounted at one end on said skip beneath said discharge opening and extends substantially vertically trom its pivot point for actuation at the other end thereof by said actuator means, said ink eing pivotally connected to said arm at a point intermediate the two ends thereof.

11. A skip adapted for travel in a mine shaft compris ing, a skip body having a discharge opening in the front wall of said skip, a dumping door pivotally mounted along the upper edge of said discharge opening, a door operating mechanism adapted when actuated to open .and close said door with a positive action, actuator means adapted to actuate said operating mechanism to open and close sai door in response to the normal travel movement of said skip, said operating mechanism including a dumping arm pivotally mounted on said skip and operatively connected to said door, said arm adapted to be pivoted by said actuator means to open and close said door, and a door locking member mounted on said dumping arm and adapted to engage the free swinging edge of said door along the bottom edge of said discharge opening as said arm is pivoted in its door closing direction to thereby lock said door in its closed position.

12. A skip adapted for travel in a mine shaft comprising, a skip body having a discharge opening in the front wall of said skip, a dumping door pivotally mounted along the upper edge of said discharge opening, a door operating mechanism adapted When actuated to open and ciose said door with a positive action, actuator means adapted to actuate said operating mechanism to open and close said door in response to the normal travel movement of said skip, said operating mechanism including a dumping arm pivotally mounted on said skip and operatively connected to said door, said arm adapted to be pivoted by said actuator means to open and close said door, and a safety hook pivotally mounted on said dumping arm and adapted to engage a keeper on said skip body to lock said door operating mechanism in its closed position.

13. A skip adapted for travel in a mine shaft comprising, a skip body having a bottom which slopes to a discharge opening in the front wall of said skip, a dumping door pivotally mounted along the upper edge of said discharge opening, a door operating mechanism adapted when actuated to open and close said door with a positive action, actuator means adapted to actuate said operating mechanism to open and close said door in response to the normal travel movement of said skip, said operating mechanism including a dumping arm pivotally mounted on said skip and operatively connected to said door, said arm adapted to be pivoted by said actuator means to open and close said door, and a bridge plate pivotally mounted on said skip beneath said discharge opening and operatively connected to said dumping arm, said plate adapted for movement outwardly from under said skip body as said dumping arm is actuated from closed to open position by said actuator means.

References Cited in the file of this patent UNITED STATES PATENTS 

